All solvents are classified as Volatile Organic Compounds due to their photo-reactive qualities and Hazardous Air Pollutant (HAPS) status. The United States Environmental Protection Agency (“EPA”) defines volatile organic compounds (“VOC's”) or “Exempt VOC's” in the Federal Register under 40 CFR 51.100(s). They are further sub-classified based upon their vapor pressures, boiling points, and flash points. The flash point is critical because it is the point at which the liquid becomes a volatile vapor, mixes with oxygen, and thereby acquires its most combustible or flammable state. In the United States, the Environmental Protection Agency (EPA) and the Department of Transportation (DOT) have classified such compounds based on their volatilities or “flash points”.
The EPA and DOT Volatile Organic Compound (“VOC”) classifications are as follows:
Class I liquids (flammable)flash point at or below 100° F.Class II liquids (combustible)flash point from 100° F. to below 140° F.Class III liquids (combustible)flash point above 140° F. to below 200° F.
Obviously, the more flammable a solvent, the more restrictions exist on its use. The Federal Government has classified such solvents as Hazardous Materials or “HAZMATS”. Further, manufacturers that utilize solvents must handle, store, warehouse, and ship the more volatile liquids more carefully and have to address issues involving atmospheric volatility, shelf life, and worker health concerns from prolonged exposure to these chemicals. If these solvents can be modified so that their flash points can be raised, this would result in significantly greater safety with respect to the handling, storing and shipping of these compounds as well as increasing their shelf lives. It is desirable therefore to raise the flash points of a variety of organic solvents without changing the solvent's strength and utility or substantially increasing its cost. This would expand the range of potential uses for these solvents.
Some terpene alcohols have the chemical formula: C10H18O. Terpenoid is the general name given to this class of compounds which are characterized by a repeating carbon skeleton of isoprene. Terpenoids are derived from plants, trees, flowers, and other vegetation which allows their classification as “green compounds”. They come in the form of liquids, solids, waxes, oils, and alcohols. Terpenoids are divided into groups determined by the number of carbon atoms and repeating isoprene units. They may be formulated into acyclic, monocyclic, or polycyclic structures.
Terpene alcohols in various forms have been used for centuries in fragrances due to their signature odor and compatibility with other compounds and their minimal negative environmental impact. The flavor and fragrance industries divide terpineols, a type of terpene alcohol, into Alpha-, Beta- or Gamma-Terpineol, with Beta-Terpineol being non-naturally occurring. Terpene alcohols have been used for other purposes, such as disinfectants, cleaning compounds, soaps, cosmetics and colognes. They are also known to add, enhance or mask the odor of products which perhaps might be offensive to humans or animals.
U.S. Pat. No. 7,273,839 B2 discloses the use of an Alpha terpineol with petroleum based organic solvents and blends of solvents to increase the flash points of these solvents. The patent discloses that the addition of at least 10%, by weight, of a single Alpha terpineol to a solvent or combination of solvents increases the flash point of the blended compound. They show that at least 5% of one Alpha terpineol increases the flash points of specific solvents to provide increased options for which these solvents may be used. In one example, they claim that by adding 18 wt % of Alpha terpineol to acetone, they increased the solvent's flash point from 0° F. to 143.6° F. However, high Alpha terpineol loadings, such as in the 10-18%, by weight, range, often may cause rapid settling incompatibility and decreased shelf life, which substantially adds to the cost of formulating and using the solvent or combination of solvents.